Charging device for a metallurgical furnace



Dec. 24, 1968 w. FADLER 3,418,019

CHARGING DEVICE FOR A METALLURGICAL FURNACE Filed Sept. 1, 1966 FIG. x

' I mm I NVEN TOR. H44 L 7'5? FZDL 2 A TFOPNXS United States Patent 13,418,019 CHARGING DEVICE FOR A METALLURGICAL FURNACE Walter Fadler,Vienna, Austria, assignor to Wiener Schwachstromwerke Gesellschaftm.b.H. Filed Sept. 1, 1966, Ser. No. 587,631 Claims priority,application Austria, Sept. 6, 1965, A 8,123/65 8 Claims. (Cl. 29471)ABSTRACT OF THE DISCLOSURE A charging device for a metallurgical furnacecomprises a tubular charging shell which is movable within a mountingring stand. The shell has a bottom closure that will be opened when theshell is moved downwardly relative to the ring stand.

This invention relates, in general, to apparatus for use with metalfurnaces and, in particular, to a new and useful charging device forfacilitating the charging of metallurgical furnaces.

It is usual to charge metal furnaces from the top by hand. The materialto be charged (scrap, chips, recirculated material, etc.) is manuallyintroduced with a shovel directly to the top charging opening into theinterior of the furnace provided for melting the metal, or, the materialis piled up at the rim of the charging opening of the furnace and it isthereafter thrown in. If the furnace for melting the metal contains somemolten material already, the operators while performing the work ofcharging the furnace are endangered by a possible spattering of themolten metal during the charging process. This danger is not evenrestricted to definite brief charging periods becaune metallurgicalfurnaces which operate at high rates require continuous charging by theoperators.

In accordance with the present invention, there is provided a chargingdevice for metallurgical furnaces, particularly for induction heatedcrucible furnaces which include a charging basket comprising a shell andmounting stand therefor which facilitate the charging of largequantities of material into a furnace without danger to the operator.

The apparatus of the invention advantageously includes a basket made upof a carrying frame, a cylindrical shell and two bottom flaps which arepivotally mounted on the shell which may be pivoted outwardly in orderto discharge the material from the shell into the furnace. In apreferred arrangement, the bottom closure for holding the materialwithin the shell advantageously includes separable flaps which are madeof a curved configuration so that there will be a tendency for theweight of the material within the container to urge the two separableparts outwardly for the dumping of the material into the furnace. Theclosure flaps are such that they may be interlocked in their closedposition and either automatically or manually unlocked when the carryingframe is placed at the rim of the charging opening of the furnace to becharged. The opening defined by the flaps is determined by the height ofthe basket over the charging opening.

In a preferred form, the complete charging basket including thesupporting frame and the shell for the charging materials is formed asan integral unit which may be suspended, for example, from a crane usinga lifting arm connected to the upper portion of the shell. In thismanner, after the shell is charged, the complete basket may be moved toa position overlying the furnace opening and lowered onto the rimthereof to facilitate the discharge of the products into the furnace.

A further feature of the construction is that the shell 3,418,019Patented Dec. 24, 1968 is suspended, e.g., by means of a hook and ropefrom a lifting gear, e.g., a crane, so that it can be lowered to anydesired level over the charging opening of the furnace to be charged.This enables a charging of a predetermined amount of material to thefurnace to be charged and consequently an extremely exact charging ofrelatively large amounts of material. As the material being chargedfalls centrally through the charging opening of the furnace the ceramiccrucible of induction heated furnaces is preserved so that a long lifefor such a crucible is insured. This is another important advantage ofthe charging device according to the invention.

In accordance with another feature of the invention, the carrying frameor support is provided with a cylindrical ring into which the shell maybe placed which sup ports the carrying arms for the separable bottomflaps which may be pivoted outwardly on these arms and additional armspivoted to the shell for discharging the material from the shell. Thebottom flaps are formed with a cylindrical or spherical interior surfacehaving a radius of curvature corresponding to the length of the pivotedarms which support the flaps. The depth of the curvature of the bottomflaps is about A of the radius of curvature. The shell is normallyconnected to the ring support through holding arms which are carried bythe inner ends of the bottom flaps and pivotally held by respectiveopposite sides of the shell. In the closed position of the flaps theholding arms extend vertically upwardly from the bottom of the shell andengage over pivot pins to hold the ring bottom flaps and shell together.The bottom flaps may be locked in a closed position by a dog which ispivotally carried on one holding arm and engages Over a pin on the otherholding arm.

The ring support member is supported on a plurality of legs which may bearranged so that they may straddle around on the rim of the furnace tobe charged. The ring platform is secured to the shell through theholding arms so that the shell and the platform may be removed toanother location for the filling of the shell with materials to becharged into the furnace. After filling, the holding arms for the bottomflaps are unlocked which permits them to open under the weight of theshell and the charging materials as the shell moves downwardly in thering support until a stop defined on the exterior thereof abuts the topof the ring element.

Accordingly, it is an object of the invention to provide a metallurgicalfurnace charging device which includes a shell member which is arrangedto cooperate with a ring support and wherein there is provided pivotalflap members for closing the bottom of the shell when it is in thesupport, the flap members being pivotal outwardly to permit dumping ofthe charge material directly into a furnace over which the support isset up.

A further object of the invention is to provide a device for charging afurnace which includes a charging shell which may be filled with thematerial to be charged in the furnace and, which includes bottom flapswhich are held together below the shell but which include curved innersurfaces which will facilitate the gradual opening of the flaps afterthey are unlocked.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of this specification. For a better understanding of the invention,its opeerating advantages and specific objects attained by its use,reference should be had to the accompanying drawings and descriptivematter in which there is illustrated and described a preferredembodiment of the invention.

In the drawings:

FIG. 1 is a side elevational view of a charging device constructed inaccordance with the invention; and

FIG. 2 is a transverse sectional view of the charging device indicatedin FIG. 1 with the bottom flaps of the device shown in an openedposition in the lefthand portion of the drawing.

Referring to the drawings, in particular, the invention embodied thereincomprises a charging device which constitutes a basket made up of acylindrical shell 2 and a support member comprising a ring which issupported on the legs 6. The cylindrical shell 2 is of a size to permitit to be freely moved upwardly and downwardly within the ring 5.

In order to facilitate moving the shell 2 within the ring 5 or liftingof the combined basket including the ring 5 and the shell, the shell 2is provided with pivot mounts 3 and 4 for a suspension gear or carryingarm 1 which, for example, may be connected to a hook (not shown) of alifting device.

A feature of the invention is the arrangement for closing the shell 2 toretain the charged materials therein until they are to be dumped into afurnace having a rim 15. In the embodiment illustrated, the bottom ofthe shell 2 is closed by flaps 7 and 8 which are pivotally mounted bymeans of rigid bracket elements 11' and 12' adjacent their outer ends onrespective arms 9 and 10 which are pivoted on respective brackets 11 and12 carried by the ring 5. The inner ends of the flaps 7 and 8 arerigidly connected to the lower ends of upstanding holding arms 16 and17. The upper ends of the holding arms 16 and 17 are pivotally supportedon the shell on pivots or trunnions 20 and 22 formed on the exterior ofat least one side of the shell. In the closed position indicated in FIG.1 the holding arms 16 and 17 extend substantially vertically and theyare locked together by a pawl 14 which is pivoted on arm 16 and engagesover a pin 24 on the arm 17. The combined basket including the shell 2and the ring 5 are connected together through the bottom fiaps 7 and 8and the pivotal connection of supporting arms 9 and 10 to the ring 5 andthe pivotal connection of the holding arms to shell 2.

After the shell is charged with material and the basket is located overthe furnace rim 15, the holding arms 16 and 17 are unlocked by openingthe dog 14 to permit the bottom flaps 7 and 8 to pivot outwardly withthe associated arms 9 and 10 in accordance with the downward movement ofthe shell -with pivots 20 and 22. In order to facilitate the outwardmovement of the flaps 7 and 8, they are formed with concave interiorsurfaces so that the weight of the material acting thereon has atendency to force the flaps to an outward opened position.

In accordance with another feature of the construction, the shell isprovided with a stop or annular ring projection 13 formed-at a locationsufficiently above the ring stand 5 to permit the shell to movedownwardly against the bottom flaps as the material is being discharged.The lowermost movement of the shell 2 is determined by the location atwhich the stop 13 contacts the ring stand 5.

In the charging position, the bottoms of the legs 6 are engaged aroundthe rim of the furnace and the shell 2 is centered over the openingdefined within the rim. The interlocking means 14 may be released byhand or automatically and the material in the shell will fall centrallyinto the interior of the furnace through the opening which is definedwihin the two bottom flaps parts 7 and 8 when they are moved apart.

The amount of material to be charged into the furnace will depend on thesize of the opening defined between the flaps 7 and 8 and this may beadjusted in accordance with the amount the shell is lowered within thering 5.

What is claimed is:

1. A charging device for a metallurgical furnace comprising a mountingring stand, a tubular charging shell within said ring movable upwardlyand downwardly relative to said ring stand, a bottom closure for saidshell comprising two separate flap members adapted to be positionedtogether below said shell for closing the bottom of said shell and beingseparable for opening the bottom of said shell, and means mounting saidbottomflap members for movement apart to open said shell bottom andmovement together to close said shell bottom, said bottom flap membersbeing pivotally mounted adjacent their one ends on said ring stand andpivotally connected to said shell adjacent their opposite ends, saidring stand including a ring member in which said charging shell isdisplaceable within the limits of the pivotal connections of said flapsto said shell, said flaps being located below said ring member when in aclosing position.

2. A charging device for a metallurgical furnace according to claim 1,comprising a mounting ring stand, a tubular charging shell within saidring movable upwardly and downwardly relative to said ring stand, abottom closure for said shell comprising two separate flap membersadapted to be positioned together below said shell for closing thebottom of said shell and being separable for opening the bottom of saidshell, and means mounting said bottom flap members for movement apart toopen said shell bottom and movement together to close said shell bottom,said ring stand comprising a ring member, leg means supporting said ringmember at a predetermined elevation, said means mounting said bottomflaps including lever means pivotal on said ring member and carryingsaid flaps adjacent their one ends, said flaps having holding anmsconnected to their respective inner ends and extending upwardlytherefrom and means pivotally holding said holding arms on said shell.

3. A charging device for a metallurgical furnace, according to claim 2,where in said flaps are convexly curved on the interior, the curvaturebeing such that weight acting downwardly on said bottom flaps tends toopen them.

4. A charging device for a metallurgical furnace, ac-' cording to claim3, including means for locking said charging flaps together to close thearea below said shell.

5. A charging device for a metallurgical furnace, according to claim 4,wherein said shell may be lowered downwardly in said ring member againstsaid bottom flaps to open them.

6. A charging device for a metallurgical furnace, according to claim 5,including an annular stop member defined on said shell at a locationabove said ring member permitting lowering of said shell until said stopmember contacts said ring member.

7. A charging device for a metallurgical furnace comprising a mountingring stand, a tubular charging shell within said ring movable upwardlyand downwardly relative to said ring stand, a bottom closure for saidshell comprising two separate flap members adapted to be positionedtogether below said shell for closing the bottom of said shell and beingseparable for opening the bottom of said shell, and means mounting saidbottom flap members for movement apart to open said shell bottom andmovement together to close said shell bottom, said ring stand includingan annular ring member, a plurality of legs supporting said ring memberat a fixed elevation, an annular stop defined on the exterior of saidshell above said ring member limiting the lowermost movement of saidshell within said ring member to the position at which said annular stopcontacts said ring member, a pivot arm pivotally connected to said ringmember at diametrically opposite sides thereof and connected torespective ones of said flap members, said bottom flaps having a portionforming a cylindrical surface with a radius of curvature which is equalto the length of said pivot arms, a holding arm connected to each ofsaid bottom flaps and extending upwardly from the ends thereof meanspivotally connecting the upper end of said holding arms to said shell,latch means connected to said holding arms for latching said holdingarms together when said flaps are in a closed 5 6 position, said shellbeing adapted to bear against the References Cited inside surface ofsaid flaps and being movable down- FOREIGN PATENTS Wardly upon releaseof said latch means and outward pivoting Opening movement to said flaps.982875 2/1965 Great Bntam' 8. A charging device for a metallurgicalfurnace, ac- 5 EVON Q BLUNK Primary Exam-Hen cording to claim 7,including a bracket secured to said ring member on respectivediametrically opposite sides GUIOD Emmme thereof pivotally supportingsaid pivot arm members for U5, CL X R said respective flaps. 214-18

